Changes

Control of BVD is practiced to a greater extent than treatment. There are several elements to control, including effective biosecurity, elimination of persistently infected animals, and vaccination strategies³⁹.

Control of BVD is practiced to a greater extent than treatment. There are several elements to control, including effective biosecurity, elimination of persistently infected animals, and vaccination strategies³⁹.

Replacement cattle should be tested for persistent infection before entry into the herd. Quarantine or physical separation of replacement cattle from the resident herd for 2-4 wk should be considered, and vaccination of replacement cattle for BVD should be done before commingling with the resident herd. Embryo donors and recipients also should be tested for persistent infection. If vaccination of embryo donors or recipients is warranted, it should be done at least 1 estrous cycle before embryo transfer is performed. Because BVDV is shed into semen, breeding bulls should be tested for persistent infection before use. Artificial insemination should be done only with semen obtained from bulls free of persistent infection.

Biosecurity measures can include the usually hygiene precautions taken on farms, by visitors and during veterinary attention, as well as scrutiny of bought-in livestock and biologicals. Replacement cattle should be tested for persistent infection and quarantined on-farm in case of acute infections before entering the herd. If the resident herd is BVD-vaccinated, new animals should be brought up to date before joining the cohort. Embryo donors should be tested for persistent infection before transfer occurs, and purchase of in-calf heifers should be avoided as their offspring may be persistently infected. BVDV is shed in semen, so breeding bulls and semen for artificial insemination should be tested before coming into contact with cows.

Screening cattle herds for persistent infection is done by virus isolation from serum or buffy coat cells, antigen-capture ELISA from serum or buffy coat, or antigen detection in skin biopsies. Several strategies, based on herd size, type of herd being screened, financial limitations of the herd owner, and testing ability of the diagnostic laboratory being used, are available to screen herds for persistent infection. When identified, persistently infected cattle should be sold for slaughter as soon as possible.

Screening cattle herds for persistent infection is done by virus isolation from serum or buffy coat cells, antigen-capture ELISA from serum or buffy coat, or antigen detection in skin biopsies. Several strategies, based on herd size, type of herd being screened, financial limitations of the herd owner, and testing ability of the diagnostic laboratory being used, are available to screen herds for persistent infection. When identified, persistently infected cattle should be sold for slaughter as soon as possible.